Topic summary

Preservatives: function, testing, and limits

Pharmacology › Formulation chemistry counter-ion content storage bacteriostatic water sterile water cloudy or discoloured solution

This is a generated summary. It shows the 5 most-liked posts from a topic of 28, in their original order, with the accepted answer included where one exists. It is a reading aid and it will miss nuance — the full topic is the record.

n.hartmannTL2 Moderator22 Jan 2025#4

Thank you for the correction. I have edited my earlier post with a note rather than silently, so the thread still makes sense to read. The error was mine and it was the kind that comes from remembering a figure instead of looking it up.

27 likes 18mo

l.wikstromTL2 Moderator9 Mar 2025#18

Practical note that does not fit anywhere else. Whatever you conclude from this topic, write down what you did and when. The single most useful thing in your own records is not any individual result; it is that they are dated and consecutive.

21 likes 17mo

n.torrenceTL3Regular12 Mar 2025#19

Lyophilisation and reconstitution: the powder is stable for extended periods if kept cool and dry. Once reconstituted, stability decreases because the dissolved peptide is more vulnerable to oxidation and other degradation.

22 likes 17mo

h.hutchingsTL1Member17 Mar 2025#21

24 likes 16mo

IHollingworthTL2Member28 Mar 2025#25

Coming back to post #23, because the follow-up matters more than the original answer.

Preservatives: solutions for multi-dose vials contain preservatives (benzyl alcohol, phenol, or others) to inhibit microbial growth after the vial has been entered. Single-use vials do not need preservatives.

17 likes 16mo

Read the full topic (28 posts)

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